Variable pitch propeller



2 Sheeus-Shea# 1 J. E. CAROL VARIABLE FITCH PROPELLER Filed Aug. 12, 1941 Feb. 8, 1944.

Feb. 8, 1944, JfE, CAROL 2,34L27 VARIABLE FITCH PROPELLER Filed Aug. l2, 1941 2 Sheets-Sheet m Patente-d8,- l l "UNITED STATES PATEN otfFFJ-lci:

i v .'la'iftlirlnornmm' i JamesE. .fCarol -Los Angeles, Calif., vassigner-hy adireet and mesme assignments. ,of sixty :per cent to (3. 'Bland Jamison, twenty Vper vcent to :Collins JMason, and twenty -per .cent .to Arthur E. Wrightfall `o1' Beverly Hills,fCali1. v

Application August .1.12, 1941, se'ria1 Nel- 406,489

(ci. .11o-.163)

6 Claims.

. vIt is among my objectsto provide-.an e'cient f variable pitch propeller vof such lightweight and economical construction that it may be made available for generaluse Aon relatively small air- 4wooden blades without any danger ofthe blades. y being thrownlinfight andv without requiring Yau vunduly large and'heavy housing; which overcomesthel diiculties heretofore experienced with thrust `-l: earings; which isinexpensive to manulfactme, durable, eflcient and of relatively :light weight.

are' accomplished will Abecome clear to those planationof apresently-preferred example otmy l invention, .although .of course it is to lbe 'understood that `within its broader scope my invention may be carried youtzbv utilizing othersneciflc forms andadaptations. Inathe following description l'. shall refer .to .the accompanying drawings, in which:

Fig. 'f1 is a front zview ,in I'longitl Fig.12 is a plan vlew -'planes. I am. aware that variable vpitchi pro- .10 Fig. 3is a section on linezpellersare'known but those have r beenof a de- Fig. -4 vis asection online `signand construction whichhavefrendered them Fig. 55 is a longitudinallsecti so-costly and heavy thattheir use is prohibitive ification. 1 i Y except upon large, powerful andv expensive air- -In'the drawings, `I yshown-a ubaunt including@ planes. One of .the principal sreasons why no 15 spindle 5 and a .tubular barrel `Il) mounted ra-4 -successful '-variable pitch 4propeller hasxheretc- .dially on the spindle, The spindlehasabore Sore been produced to illl the needof small airl and -s secured longitudinally on .the drive vshaft planes is the flack of a solution of the problem S of a motor notshown, and extends-.transversely ofhow wooden ypropeller blades :may be used `in through the central -holes lof the barrel, .ibeing such Vdevices withoutithe blades ,being-thrown 20 ysplined thereto at A8.v On leach end vof fthe'barrel by virtue of the great centrifugaiiorces'attendf l0, I thread acollar 15|, each of whichcollars ing operation. Another shortcoming of .-prior has an inwardly projecting annularange ,ljlsa devices hasv been the-practical .diiculties Vof itc house the'thrustb'earing to be laterdescribed.A changing the `pitch ofsthe blades while infight-/ Adjacent `the inner end of each of -the .collars .|;I

that is, .the tremendous .centrifugal and other 25 I provide through the vbarrel apairoidiamet- .forces presentsin normalpropeller operaticnhave rically opposite .circumferentially disposed slots -rendered the pitch changing means'inoperable t5 for fthe vpurposes to be described.

or impracticable 'Furthermoreg the arrangelI n eachend of the barrel 10,1 mount the shank ments andtypesof bearings utilized in suchdel2li of a woodenpropeller 4b1ade l?. 1I have said vices'have proven :incapable of withstanding the -30 that adifculty -withzprevious attempts to `utistressesand vibrations :attendingfnormal operalize wooden blades in variable :pitch mechanisms tion. A still further shortcoming -of vprevious vhas been the inabilityofsuch structures toprevdevices attempting :the use oif l wooden blades -ven't throwing of theblades whllein operation. has Yb`een.:the inability to provide shank ends'of 1 have successfully overcome vthis ,dimculty "by I the blades vof sumcient size to .withstand 'the '35 utilizing, as an element `of my combination, a breaking .moments without .making 4the hub vfeature shown in my kcopending :application Sevstructure so large and lheavy as Atobe impracria1Number'395,398. 'Each 'blade `shank isprgticable. vided with an annular recess L22 .of V-shaped "It is Ato Athe 'overcoming of 'these and'fother zlongitudinalsection, and inthis recessizzrmount-a fatal shortcomings -.ojf theprior art that imy fin- 40;sp1it sleeve 25 having an inner 'surface .of 1y vention:is-primarily-directed,and among itsobfshajped longitudinal section to conform `to the jects I airn to provide "a variable pitch propeller .recess inthe shank, diametrically opposite holes which maybe manually operated `1.1:orntl'le"air vv26 being provided through .sleeve 15in :register plane cockpit during 'night to vary rthe V*pitch with slots I5. vA vferrule .30 houses -leach :shank .angle of the blades; which successfully utilizes 45 20 with its carried sleeve .25 and each :ferrule is provided with holes ,3l in register -with holes 26 andfslots I5 to receive the loperating pin to. be 'later described. Annuler bearing .races 1l are `provided in eachferrule, -a-t O Dpositeeides of holes 3|, to take bearing rollers 35;'

A -fhole It) is provided Ithrough veach blade shank 20, in registry .with :holes-G, 131 fand slots l5, and through each `of these jholesiinsert a cross pin l2', 4211, the-ends of lwhich:project ont-` wardly beyond the plane of :the youter .barrel surface through: holes 45a in ringsf45 rotatably mounted on the barrel over the slotsy i5. At one end each of the pins 42, 42d'has a spherical head 46 and carries a washer l47| and threaded nut 48 at its opposite end to securel the pin against longitudinal escape. -etween l the outer surface 45h01 each ring andthe inner surface IIb of each collar Ii,- .Lprovide an annular thrust bearing consisting of a ball- .carrying ring 50 and an outer bearing lrace ring 50a. The flange Ila previously described overhangs this thrust bearing membrane` l* Each ferrule 30 preferably has a ilaredhuter end 30a which fits over the relatively enlargedl portion of the blade adjacent the shank From the foregoing it will be observed that each blade shank 20, together with its carried nular recess 85 is also provided in each'ferrulef'?" A split ring I6 nts in recess 85 and is held therein by. theI overhanging portion 81a of inner thrust bearing race ring 61. The outer bearing race ring 88 is held against longitudinal movenient by threaded ring 89, the barrel being of relatively. increased diameter at and adjacent f its outer'ends'to take the ring, and the thrust bearing members. A' cross` pin 90 extends through each end l,lof the barrel as well as each fernlle, sleeve 25 and shank in the manner before-described, andprojects at its ends through circumferenti'ally disposed slotsy 8|, along which sleeve 25 and ferrule 30 is rotatable -about'its 1 longitudinal axis in the barrel to thevextent o fy the length of the slots I5, the ends of the slots acting as stops for the cross pins 42, 42a;

angle, `I provide links 60, 6|,.each of whichi is universally mounted at one end on the spherical f end 46 of a cross pin and islikewise mounted at its opposite endon one of the-two radially disposed arms 64'of a push plate 65. Plate 651s secured on a sleeve 61 which is slidably mounted on spindle and-held against rotationwith respect thereto by a key and keyway 68. VSleeve 61 has an annular flange 10, and a pair of spaced thrust bearings' 1I, 1i.4 are mounted on the. sleeve between vthe flange 10 and plate. 65. A j yoke 'I5 fits astride sleeve 61 between bearing members 1h12 and a push rod-80 is secured at one end to -the yoke and extends. at its other end into the cockpit of the airplane so `that it may be manually operated to vary the pitch angle of the blades. To change the blade pitch in one direction, "yoke is urged against bearing 12 to move `plate=65, links 60, 6l andppins 42 forward, and to change the blade pitch in the opposite direction said parts are operated in the -.op posite direction.y z

From theforegoing it'will be seen that the blade shank may be of relatively large. diameter and yet the outside diameter of: the barrel. is

relatively small because the thrust bearing 'is'.

exterior of the barrel-instead ofbeinginterposed between the shank and inner surface of the barrel. Furthermore.v a maximum thrust bearingsurface is provided, which is conducive to easeof operation.y It is also impossibleto throwv"a blade because pins 4Z, 42a extend medially 'through the Shanks,v sleeves 25 and .55 ferrules and evenif centrifugal pull on the atl Y about its longitudinalaxis in the casing, and4 slots the vpin'moves torotate the ferrule and its, carried .shank when .pushed or pulled by the operatin'g'flinks 95. Links 85 are the same as links'.60,f6ll and are'operated by the same means as. before described.

f Whiiel have resortedto considerable detail 261m describing these particular adaptations, I have For rotating the-blades to vary `their pitch done so only to make my invention clearly understandable, Other modificationsI and adapta,-

' tions maybe made within the 'broaderscop'f my invention as dened by the followinglai'ins. l. A variable pitch propeller comprising" in combination with a hub having a transverse bore"y adapted to receive a driven shaft and a 'tubular' casing. disposed radially of the bore, an annular* thrust bearing encompassing the casingfexterior, i" a blade having a shank mounted for` rotationvz means for rotating the blade including'alproj Jection extending radially ,from the 'and having bearing engagement with th'e thrust".r beating. y

2. A variable pitch l propeller 'con'lprlsihgI j combination with a hub having ,a .transverse bore adapted to receive a driven sheLftancll a.

cumferentlally around the casing, a blade hav tudirxal axis" in the, casing, and means for rotate.

radially from the shank and having bearing `tubular casing disposed radiallyof the1bore,`an' annular vthrust bearing encompassingftle'. cas;

ing exterior, said bearingbeingrtatable 'cir- .l

ingaslhank mounted for rotation about its lo'ngi i118 the blade including a Drojection extending' ensagement within the thrust bearing,

3. A variable pitch propeller comprising ma.

combination with a hub having a transverse borej adapted to receive a drivenshaftrand a tubularl casing rdisposed radially ofV the' bore, an annular thrust bearing encompassing the casing exterior,

a blade having a shank having a tapered annublades should tend to elongate the cross-section of the holes through the wooden Shanks, the tapered inner/surface of the sleeve, which sleeve is held against longitudinal movement by the cross pin, would-compress the inner end of the shank' to further strengthen the structure'. -1

In the device of Fig.` 5 I show a barrel or hub l0' disposed radially on the spindle 5', each end ofthe barrel .having a longitudinal bore into each ofgwhich bores-'a' blade shank carryingferlar slnface, a longitudinally split sleeve encom-l e passing and conforming to said annular sureA face, a ferrule constricting, .the sleeve about'th'e... shank, said ferrule being rotatably mounted in" the casing, and means for rotating the ferrule relative` to the casing. whereby to rotate the blade, said means-including. a pin extending di- .'ametrically; through the shank, sleeve, ferrulelv rule 30" is vrotatably mounted, a tapered split.4

sleeve-25' being interposed between the shank.. and `ferrule asA before described. 'I'hemedialy portion 80 ofthe barrel is solid and presents at each side a projection 8i -on which is mounted.-v a roller pilot bearing 82, the outer race member fof which ts against the inner surface ofi-the ferrule. The ferrule is provided with an annularrace B2i carrying bearing rollers`84 and .an anandv casing -and having bearing engagement 'at its outer end with the thrust bearing. 5 v i 4. A ',Valfiable pitch propeller comprising 'ink combination with a hub having a transverse' bore .adapted to receive a driven shaft and a tubular casingY disposed radially of the bore, an annular thrust bearing encompassing the casing exterior, va. blade having agshank having'a tap- .,ered annular surface, a longitudinally splitY sleevevencornpassing and conforming to said an. Vnular surface, a ferrule constricting the sleeve l about the shank, said ferrulebeing rotatably mounted inthe casing, pin ymeans Yprojecting radially from the ferrule through the casing and having bearing engagement' with the thrust bearing, and a pair of radial bearing members disposed between the ferrule and the interior surface oi-the casing, said radial bearings being disposed one on each side of the pin means.

5. A variable pitch propeller comprising in combination with a hub having a transverse bore adapted to receive a driven shaft and a tubular casing disposed radially of the bore, a ring a projection extending radially from the shank through the slot and having bearing engagement with the thrust bearing 6. A variable pitch propeller comprising in combination with a hub having a transverse bore adapted to` receive a driven shaft and a tubular casing disposed radially of the bore, an annular thrust bearing encompassing the casing exterior, a circumferentially disposed slot in the casing, a ring rotatably mounted on the casing in position covering the slot, said ring having bearing engagement with the thrust bearing, a blade having a shank mounted for rotation about its longitudinal axis in the casing, and means for rotating the shank including a pin projecting radially from the shank through the slotl and being secured at its outer end to the ring.

JAMES E. CAROL. 

